For radiocarbon dating to work, the object being tested must (1)have been made out of rock (2) have gold as an element (3)have been alive at one time (4) be at least 10,000 years old

Of the pollutants that form acids in the atmosphere, which is easiest to reduce? a. sulfur dioxide b. nitrogen dioxide c. ozone d. carbon monoxide

Question 1 of 102 pointswhich best describes adaptive radiation? oa. geographical isolation caused by an adaptationob. biodiversity resulting from few ancestorsoc. a decrease in the rate of speciationd. adaptations that organisms teach each other

Which of these substances does not protect against invaders in the nonspecific immune response? a. saliva b. mucus c. tears d. urine